/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#ident  "%Z%%M% %I%     %E% SMI"

#if defined(lint)

typedef long *jmp_buf_ptr;

#else   /* lint */

#include <sys/asm_linkage.h>

#endif  /* lint */

/*
 * _setjmp(buf_ptr)
 * buf_ptr points to a five word array (jmp_buf). In the first is our
 * return address, the second, is the callers SP.
 * The rest is cleared by _setjmp
 *
 *              +----------------+
 *   %i0->      |      pc        |
 *              +----------------+
 *              |      sp        |
 *              +----------------+
 *              |    sigmask     |
 *              +----------------+
 *              |   stagstack    |
 *              |   structure    |
 *              +----------------+
 */

#if defined(lint)

/* ARGSUSED */
int
_setjmp(jmp_buf_ptr buf_ptr)
{ return (0); }

#else   /* lint */

        PCVAL   =       0       ! offsets in buf structure
        SPVAL   =       4
        SIGMASK =       8
        SIGSTACK =      12

        SS_SP      =    0       ! offset in sigstack structure
        SS_ONSTACK =    4

        ENTRY(_setjmp)
        st      %o7, [%o0 + PCVAL]      ! return pc
        st      %sp, [%o0 + SPVAL]      ! save caller's sp
        clr     [%o0 + SIGMASK]         ! clear the remainder of the jmp_buf
        clr     [%o0 + SIGSTACK + SS_SP]
        clr     [%o0 + SIGSTACK + SS_ONSTACK]
        retl
        clr     %o0
        SET_SIZE(_setjmp)

#endif  /* lint */

/*
 * _longjmp(buf_ptr, val)
 * buf_ptr points to an array which has been initialized by _setjmp.
 * val is the value we wish to return to _setjmp's caller
 *
 * We will flush our registers by doing (nwindows-1) save instructions.
 * This could be better done as a kernel call. This is necessary to
 * ensure that the registers we want to pick up are stored in the stack.
 * Then, we set fp from the saved fp and make ourselves a stack frame.
 */

#if defined(lint)

/* ARGSUSED */
void
_longjmp(jmp_buf_ptr buf_ptr, int val)
{
        return;
}

#else   /* lint */

        ENTRY(_longjmp)
        save    %sp, -WINDOWSIZE, %sp
        !
        ! flush all register windows to the stack.
        !
        set     nwindows, %g7
        ld      [%g7], %g7
        sub     %g7, 2, %g6
1:
        deccc   %g6                     ! all windows done?
        bnz     1b
        save    %sp, -WINDOWSIZE, %sp
        sub     %g7, 2, %g6
2:
        deccc   %g6                     ! all windows done?
        bnz     2b
        restore                         ! delay slot, increment CWP

        ld      [%i0 + SPVAL], %fp      ! build new stack frame
        sub     %fp, -SA(MINFRAME), %sp ! establish new save area
        ld      [%i0 + PCVAL], %i7      ! get new return pc
        ret
        restore %i1, 0, %o0             ! return (val)
        SET_SIZE(_longjmp)

#endif  /* lint */